Control apparatus for vehicles equipped with speed responsive clutches



Feb. 9, 1960 R. BINDER ETALv AT 2,924,313 CONTROL-APPAR Us FOR VEHICLES EQUIPPED WITH SPEED RESPONSIVE cLuTcHEs Filed July so, 1957 5 Sheets-Sheet l Feb. 9, 1960 R. BINDER ETAL v 2,924,313

CONTROL APPARATUS FOR VEHICLES EQUIPPED WITH SPEED RESPONSIVE CLUTCHES Filed July so, 1957 3 Sheets-Sheet 2 )Ulli I lav/770A .sw/76H l I 46' 75 I j i i ff? 3 v 56 Feb. 9, 1960 SPEED RESPONSIVE CLUTCHES Filed July 30, 1957 R. BINDER ETAL 2,924,313 coNTRoL APPARATUS FOR VEHICLES EQUIPPED WITH 3 Sheets-Sheet 3 I D 4f 35 l fz: 3/ f T ry A United States Patent Oiice CONTROL'APPARATUS FR VEHICLESEQUIPPED WITH-SPEED RESPONSIVE cLUrcHEs Richard Binder," shweinfrt; amrrmnzivitoisef von' Bom'- hard, Schweinfurtmin); Germany, assig'nors to Fichtl automotivefvehicles` and more particularly torrimproved apparatusfor controlling theoperation-of a clutchV of the type which is.` automatically.v engaged andvdisengagedin accord a'nee Wi-'Ytheengine-speed,the-c1utch beingdisengaged j Whenever`l` the -engine' speed" drops belowa predetermined value; p

lathe-type tif-controlv system'for which the invention issuitable; the engine is connected-with the transmission through 'afclutch=whiehautomatically engages when the engine? speed-is1inereased-fromits idling speed; as when the vehi'oleisfstandinga still,- to af minimum running speed for the Vengine aty which speedlthe engine isk able to take over theeload involved; in propelling -the vehicle without y dangeri of 4stalling-. Engine speed responsive clutches lof this* character -areknown-imthe-art and maybe actuated( by- -'centrifugalfforees'acting' on 1 Weights, by electromagnetic means controlled by variations in generator voltage or any other arrangement` whereby` the clutch willV always be vengaged.'tv vheneverf-the"engine speed exceeds a prede` terminenl minimumY-value' Clutches of-this-character are ordinarily 'provided'v with automatic disengaging Y meanscontrolled by the gearl shift lever while changing` gears, the disengagingmeansbeing-.power operated or otherwise arrangedto diserigage the clutch while the'engine speed is higherthan. the predetermined minimum speed and thel clutchfiwould otherwise remainr engaged. i

Theinvention-comprisesmeans for increasing the idling speed of theenginejabove-its normalYidling-speedso that the'clutch cannotbe disengagedexcept during.gear'fshifting'whilethespeedofthe vehicleis higher than a certain predeterminedminimum Value. In other words, the engine speedcontrolledmeanscfor engaging and disengaging the`clutchwisr'"eiectively-locked `out while the-vehicle is travelingat anyspeed higher than La very slow speed.

By locking outatheengine speedcontrol for the clutch, the drag of-theengineis-always available for braking purposes. For descending steep grades, a low speed gear ratio may-.beused--without danger of the clutch failingto become' reengaged after thegear` shifting-.disengagement interval. VFurtherrr1ore,=while.the engine speedresponsive clutch 'controhis thus locked out, there isv no possibility of sudden-engagement anddisengagement of the clutch by changes in engine speed while the vehicle is traveling fat nrmldriv-ing speedsf- Thissudden engagement vand' disengagement may occur if Ythe enginey speed should be permitted'f to-fdrop.to itsfidlingu speed while shifting gears withthe'-vehicle'traveling at normal driving speed.

With `the clutchtemporarily' disengaged during move# nient of'the gear shift lever, and with the accelerator in its id-lingposition; -theiengineY speed can quickly drop to its'fidling :value while thel clutch is thus disengaged. In the meantime the vehicle coasts at normal driving speed. Whenvtheenginespeed'isagain increased, Yas soon as the engi-nefspeedresponsive mechanism reengages the clutch,- the"enginisabrupdyfvconnected-to a fastmow'ng load' so that the engine drag andinertia of the engine, com'- 2,924,313 Patented Feb. 9, 1960 biaedr with 'the 'hierna oftheioving vehicle? pfduee a suddenclit'tge'inl traction at'the wheels.l Thissudden jolt ycantheunpleasant and maybe'v'ery dangerous when drivingo`lslippeyf'rad 'surfaces Tlielock o't featurel of the present invention prfever'its' this" possibility.

The'-` inventionV provides a i vehicle speed responsive switch which' is actuated` atall times when' the vehicleV speed's'exceeds ar predeterminedslow'speed. When the vehicle'f'sped switch isl actuated, a"diler'ent"idlingladjust-r` ment is electromagnticlly establish'edat'the" carburetor so that minimum no load s peed'nof the engine is` main-A tained4T higher thani the"l enginief sp'edfa'f which'ftlie "clutch can becomedisengaged. The engine"speedrspoiisive control of; the clutch isf thisflocld out yvli`e"1ieverv the" vehicle is 'l' moving 'at' 'normal driving' spfe'eds."r While the vliicleiis stopped, is movingveiy slwly,' o`r"i'sd`"accelerat' in'gto` normal driving sp'ee'd5hthe 'engine' speed responsive control of the clutch' isffully effective. Vnoted' above, however, th'e'eiigine speed"rspiisi`ve control'of'the'clutch becomelslocked out as' soon as 'the' vehicle attaiiisf a pre? determined drivingspee'd'and'" remains locked Oiltv for higher vehicl Speeds."

A-prinaipai object 'of' the Lifi*venian*istria prevmien'bf example.

Still --atheir object 'offtlie'f"iiive'ntitni` `is'the"provision of a` carburetor; sitable'fo'r 'use in the novel propulsion the loweriidling s 'applied so that the full idrag ofthe enginis'i'avalable for su;spleineitaryk braking f action vregardless' of the 'vehicle `speed.

Other objects, featuresar'id adva `-tages of ,the'invention willfbec'ome apparent uponreading" l a part hereof.

Referring to the drawing.

Vl-figurefl jis a diagrammatic representation of/tlzie pro-y pulsion system for a ve'hiclefillust'rati'ng'f'an` embodiment of the/invention.-

Figure 42 is an *enlarged diagrammaticzview Aof 'the idling speed *changing apparatus in its normal or'k low Ispeed conditions," as withv the vehiclei"stoppedandf with the carburetorv positioned for low idling speed so that fuel consumption is at its minimum'valu'e. i

Figure3 issimilar 'toFigQL with fthe parts shown in their respective'positions for normaldriving speeds of thesvehicl'e, whereby the engnespeed responsive control ofthe'` clutch is lockedl outQ-the carburetor being positioned fortrhe higher idling speed. n i

Figurel4 is a vie'wsimilar' to Figl3,sl1`owing"a modi-v ed form ofthe invention wherein theloc'kout `feature is, additionally controlledby operationof the vehicle brake pedal; v i i Referring to Fig. 1, there is a diagrammatic showing of a vehicle having front wheels 10 and rear" wh'e'elslllV sections 12'an`cl la differential' 13 to a drive shaftfilSf Thedriveshaft 15is connected through a'transmissionV i l l n Y y following specifi-` cation together with the accompanying"drawingforming 16 anda clutch 17 to an internal combustion engine 18;`

The transmission 16 is provided with a manually operable lever 20 for shifting gears. Operatively associated with the gear shift lever 20 isa pair of electrical switch contacts 22. The contacts 22 are normally open and `are closed during manipulation of the gear shift lever 20 to change gears. Whenever the gear shift lever I 20 is displaced from its neutral position or `from any gear ratio selecting position,` the contacts 22 close and remain closed until the. lever 20 has reached its nal gear selecting `position or neutral, as the case may be. Switches for this purpose are known in the art and any desired form of construction may be used.

The contacts 22 control an energizing circuit 23 for y,

the operating winding 24 of a `solenoid valve 25. A

sumption permitted by the carburetor buttery valve 5, 39 is at its minimum. The engine speed corresponding to the partially open valve position shownrin Fig. 2 isV such that the clutch 17 will always be disengaged.

With the vehicle moving and the contacts of the vehcle speed responsive switch37 open,-the solenoid 33 is y deenergized and spring 48 displaces the movable abutsuction operated cylinder 27 is connected through the solenoid valve 25 and a suction line 28 tothe intake manifold of the engine 18. v When the gear 'shiftrlever actuated contacts 22 are closed, the suction'line 28 from manifold `30 is connected to the cylinder 27. The cylin-v der 27 is shown mechanically `connected to the clutchV 17 as indicated by a dotted line. With suction applied to the cylinder 27, the clutch 17 wi1l be positively dis.- engaged regardless of the` engine speed.k The clutch 17 comprises conventional means (not shown) for causing it to become` engaged whenever the speed of the engine 18 exceeds a predetermined minimum speed suicient tofv prevent stalling. Conversely, the clutch 17 becomes automatically disengaged whenever the speed of engine 18,`

drops below this minimum speed. Y

The general features of the system thus farl described ment head 46 leftwardly tothe position shown in Fig. 3.

This produces a counterclockwise displacement` of the idling position of position bell crank lever 40 by engage i ment between the head 46 and an adjustable stop screw 52. In this condition, the partially closed buttery valve 39 is openfto a greater extent thaniin Fig.2 and the minimum idling speed of the engine is increased so that the clutch' 17 will remain engaged at all times except when temporarily disengaged by suction cylinder 27 during e gear shifting. In this manner theengine speed is constrained to remainhigh enough `at all times to keep the' clutch 17 engaged so that deenergization `of the solenoid 33 `effectively locks `out the engine-speed responsive means for'engagement and disengagement of the 'clutch 117. Under these conditions, with clutchl 17`1disenare shown in greater detail in my U.S. Patent No. Y

2,800,208, issued on July 23, 1957.

The intake manifold 30 issupplied with a fuel-air` mixture bymeans of a carburetor 31 shown in greater detailin Figs. 2 to 4. The idling speed of the engine` 18 may be increased from a low speed at which clutch 17 remains disengaged to a higher speed at which clutch 17 will remain engaged by the energization of a solenoid:` This solenoid actuated mechanism for changing the idling speed is more fully described below in connectionV with Figs. 2 and 3.

The solenoid 33 is connected in an energizing circuit which extends from a grounded battery 34 andthrough ignition switch 36 to the solenoid 33. The solenoid energizing circuit is completed through conductor 35 which is connected to ground through avehicle speed responsive switch 37. Thus, whenever the ignition switch 36` is turned on, the solenoid 33 is under control of the vehicle speed responsive switch 37. The vehicle speed responsive switch 37 is mechanically connected to the drive shaft 15 by gearing within the transmission 16. This is indicated in Fig. 1 by a dotted line and in Figs. 2 to 4 by showing the switch 37 mounted on the transmission 16. The contacts of the switch 37 are closed when the vehicle is standing still or moving slowly. When the vehicle reaches itslowest normal running speed, the.`

switch 37 opens and remains open at higher speeds.

`gaged while shifting gears with the vehicle moving at' normal driving speeds, at which time the engine 18 would otherwisebe free to slow down to its clutch disconnect-` ingV idling speed in the absence of sufficient accelerator` *.l pedal pressure, the head 46 holds ythe buttery valve 39 suiciently open so that clutch engaging engine speed is positively maintainedindependently of the accelerator pedal.

In a modified embodiment of the invention shown in i Fig. 4, provision is made to obtain `the full braking action The carburetor 31 comprises the usual buttery valve 39 controlled by a bell crank lever 40. The bell crank lever 40 `is biased in a clockwise direction to` close thev buttery valve 39 by a tension spring 42. A control rod 43 extends to the usual accelerator pedal (not shown) to open the valve 39.

With no pressure on `the` accelerator pedal the bell crank lever 40 is forced by the spring 42 into eitherof two idling positions in which the buttery valve 39 1s partially closed. K -f The core `of the solenoid 33 is connected to a rod 45 which terminates at its free end in an enlarged abut-V ment head 46. The rod 45 is surrounded by a helical.

Y compression spring 48 which urgesthe head `46 towardA the left as viewed in Figs. 2 and 3. When solenoidl33 is energized, as with the vehicle standing still or moving, at slow speed, Athe displaceable abutment; head of theA engine by shifting from the `higheridling speed to the lower idling speed even though the vehicle is initially traveling at a normal driving speed.

As shown in Fig. 4 the foot brake pedal 54 `is connected through a spring 55 toa switch 57. The switch i 57 is provided with normally `opencontacts which close whenever pressure is applied to-the brake pedal 54 for slowing down the vehicle. The switch 57 may be the usual stop light switch provided with additional separate contacts for controlling the solenoid 33. vWhen pressure is applied to the brake pedal 54, the `solenoid 33 is ener-` gized, thereby making the lower idling speed effective independently and regardless of thevehicle speed. In this way,Y the full engine drag is available until the vehicle slows down to a speed Vwhere the clutch 17 disengages.

` At such` speed, the vehicle is moving slowly and the supplementary braking action of the `engine `drag is no longer` required. p

While we have shown what weibelieve to be the best embodiments of our invention, it will be apparent to those skilled in the art that changes and modifications may be made therein without departing from the spirit and scope of the invention as defined in the appended claims.

What is claimed is: Y

1. A propulsion system for avehicle, comprising in combination: an engine; controllable means for varying the speed of said engine, said controllable means including selectively oper-able means for limiting said engine speed to iirst and second different minimum idling speeds,

a speed responsive clutch `connected to said engine, sald clutch becoming engaged when said engine speed exceeds a predetermined engagement speed higher than said `first idling speed andlower than said second idling speed,v said clutch being disengaged `when said `engine speed is lower than said engagement speed,`a transmission oo nnected to said enginethrough said clutch, said transum-` arriesgarse 52 sionf including a gear shiftleverfor'felianging gearatos within -said`l transmission;A meansconnecting said transmissionA to-propelsaidvehiclegfirst? control meansbperatively associated withsaid-gearshiftlever; saidlirsticontrol means IbeingI actuated-during gear* sliifting movement thereof; means controlled by actuation-of said'frst control means for disengaging said clutch while said engine speed exceeds said clutch engagement speed; and second control means responsive to the road speed of said vehicle, said second control means being connected to said selectively operable means to limit said minimum engine speed to said first idling speed when said vehicle is moving at a slow road speed including stoppage thereof and to limit said engine speed to said second idling speed when said vehicle is traveling at speeds exceeding said slow speed.

2. In a vehicle propulsion system comprising an engine, a carburetor supplying fuel to said engine and having a controllable valve for varying the speed of said engine together with means yieldingly urging said Valve toward a partially closed position for operating said engine at a first idling speed, a clutch connected to said engine, engine speed responsive means connected to cause selective engagement and disengagement of said clutch in response te variations in said engine speed, respectively, above and below a predetermined engine speed higher than said first idling speed, a transmission connected to said engine through said clutch, said transmission being connected to drive means for propelling said vehicle, said transmission including a gear shift lever for changing gear ratios within said transmission, circuit means actuated \by said gear shift lever during gear shifting operation thereof for disengaging said clutch when said clutch would otherwise be engaged by said engine speed responsive means, the provision of vehicle road speed responsive means actuated when the vehicle speed exceeds a predetermined slow speed, and further circuit means controlled by said vehicle speed responsive means and connected to said carburetor for increasing the eX- tent of said va'lve opening when said valve is in said partially closed position thereof to provide a second engine idling speed, said second idling speed being higher than said predetermined speed with respect to which said clutch engagement and disengagement occurs.

3. A propulsion system for a vehicle, comprising in combination: an engine; controllable means for varying the speed of said engine, said""controllable means including selectively operable means for limiting said engine speed to first and second different minimum idling speeds, a speed responsive clutch connected to said engine, said clutch becoming engaged when said engine speed exceeds a predetermined engagement speed higher than said first idling speed and lower than said second idling speed, said clutch being disengaged when said engine speed is lower than said engagement speed, a transmission connected to said engine through said clutch, said transmission including a gear shift lever for changing gear ratios within said transmissions; means connecting said transmission to propel said vehicle; first control means operatively associated with said gear shift lever, said first control means being actuated during gear shifting movement thereof; means controlled by actuation of said iirst control means for disengaging said clutch while said engine speed exceeds said clutch engagement speed; second control means responsive to the speed of said vehicle, said second control means being connected to said selectively operable means to limit said minimum engine speed to said first idling speed when said vehicle is moving at slow speed including stoppage thereof and to limit said engine speed to said second idling speed when said vehicle is traveling at speeds exceeding said slow speed; a brake member for braking said vehicle, and third control means actuated by braking actuation of said brake member, said third control means being connected to said selectively operable means to limit said engine speed to said first ingselectively. operablemeans for; )limiting said-enginespeed to first and second V different idlingspdsj" a speed responsive clutch connected `to said engine, said clutch becoming engaged when said engine speed exceeds a predetermined engagement speed higher than said first idling speed and lower than said second idling speed, said clutch being disengaged when said engine speed is lower than said engagement speed; a transmission connected to said engine through said clutch, said transmission including a gear shift lever for changing gear ratios within said transmission; means connecting said transmission to propel said vehicle; first control means operatively associated with said gear shift lever, said first control means being actuated during gear shifting movement thereof; means controlled by actuation of said first control means for disengaging said clutch while said engine speed exceeds said clutch engagement speed; second coiitrol means responsive to the speed of said vehicle, said second control means being connected to said selectively operable means to limit said minimum engine speed to said rst idling speed when said vehicle is moving a-t slow speed including stoppage thereof and to limit said engine speed to said second idling speed when said vehicle is traveling `at speeds exceeding said slow speed; a brake pedal for braking said vehicle, and third control means connected to said selectively operable means along with said second control means, said third control means 4being connected for actuation by 'braking displacement of said brake pedal to render said first lower idling speed effective independently of said second control means and regardless of the speed of said vehicle.

5,. In a vehicle propulsion system comprising an engine; a carburetor supplying fuel to said engine and having a controllable valve for varying the speed of said engine together with means yieldingly urging said valve toward a partially closed position for operating said engine at a first idling speed; a clutch connected to said engine; engine speed responsive means connected to cause selective engagement and disengagement of said clutch in response to variations in said engine speed, respectively, above and below a predetermined engine speed higher than said first idling speed; a transmission connected to said engine through said clutch, said transmission being connected to drive means for propelling said vehicle, said transmission including a gear shift lever for changing gear ratios within said transmission; circuit means actuated by said gear shift lever during gear shifting operation thereof for disengaging said clutch when said clutch would otherwise be engaged by said engine speed responsive means, the provision of vehicle speed responsive means actuated when the vehicle speed exceeds a predetermined slow speed; further circuit means controlled by said vehicle speed responsive means'and connected to said carburetor for increasing the extent of said valve opening when said valve is in said partially closed position thereof to provide a second engine idling speed, said second idling speed being higher than said predetermined speed with respect to which said clutch engagel ment and disengagement occurs; a brake pedal for retarding said vehicle, and means actuable by braking operation of said pedal and included in said further circuit means, said last-named means rendering said circuit means ineffective to increase said valve opening independently of said vehicle speed responsive means.

6. A propulsion system according to claim 1, wherein said controllable means comprises an electromagnetic device having an energizing circuit for actuation of said selectively operable means and in which said second control means` inc1udcs an electxic switch connected n- 2,739,678 said energizing circuit., i Y 2,742,123

3H v r- 1 2,742,987`

u References Citcd intherle of this patent 2,747,848

Y UNITED lSTATES PATENTS l j 51'` 2,766,862 mmm Maybach Aug.`9, 193s` 217962854 2,134,520 Kliesratli Oct. 25, 1938` 8, Parker Mar. 27. 1956l Bxline Apr. 17, 1956 Mottct a1. Apr. 24, 1956 Kehoe c May 29, 1956 Binder Oct. 16,v 1956 I Lazzereschi et a1 -2-- June 25, 1957 

